I assume you understand what rule resolution is for a given rule of a specified rule type. When you want to mimic the same process for multiple rules (with different rule names) for a given rule type, you can use this feature in report definitions to achieve it. Thus, for a given set of rules of that rule type, each rule is rule resolved and the resolved rules are returned.
For executing a specific rule, we do rule resolution (including when you want to open a rule). This is done by the engine code (Java) in the platform. But if someone wants to run a report to find all the rule resolved rules based on their application and ruleset stack, checking this option and executing a report against all rules (Data-Rule-Summary) or specific rule (any Rule- class) would give the right results.